Hitachi X200 Series instruction manual 26, PID ON/OFF and PID Clear

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PID ON/OFF and PID Clear

Operations and Monitoring

The PID loop function is useful for controlling motor speed to achieve constant flow, pressure, temperature, etc. in many process applications. The PID Disable function temporarily suspends PID loop execution via an intelligent input terminal. It overrides the parameter A071 (PID Enable) to stop PID execution and return to normal motor frequency output characteristics. the use of PID Disable on an intelligent input terminal is optional. Of course, any use of the PID loop control requires setting PID Enable function A071=01.

The PID Clear function forces the PID loop integrator sum = 0. So, when you turn ON an intelligent input configured as [PIDC], the integrator sum is reset to zero. This is useful when switching from manual control to PID loop control and the motor is stopped.

CAUTION: Be careful not to turn PID Clear ON and reset the integrator sum when the inverter is in Run Mode (output to motor is ON). Otherwise, this could cause the motor to decelerate rapidly, resulting in a trip.

Option	Terminal	Function Name	State	Description
Code	Symbol
23	PID	PID Disable	ON	Disables PID loop execution
			OFF	Allows PID loop execution
24	PIDC	PID Clear	ON	Force the value of the integrator to zero
			OFF	No change in PID loop execution
Valid for inputs:		C001~C005		Example (default input configuration shown—see
Required settings		A071		page 3–49):

Notes:		PIDC	PID
• The use of [PID] and [PIDC] terminals are	5	4	3	2	1	L	PCS	P24
optional. Use A071=01 if you want PID loop
control enabled all the time.

•Do not enable/disable PID control while the

motor is running (inverter is in Run Mode).

• Do not turn ON the [PIDC] input while the motor is running (inverter is in Run Mode).

See I/O specs on page 4–6.